Effects of in utero exposure to di (2-ethylhexyl) phthalate on reproductive development in female offspring

抄録

The main purpose of the study is to evaluated reproductive development of female offspring rats after maternal exposure to di (2-ethylhexyl) phthalate (DEHP). On gestational day (GD) 12 pregnant Wistar rats were weight ranked and randomly assigned to 5 groups (10 dams per group). From GD 12 through GD17 each dam was dosed daily by gavage with either corn oil (vehicle control, 1mg・kg-1・d-1) or DEHP (1, 250, 750, or 1000mg・kg-1・d-1). Then female offspring were monitored for eye opening, organ coefficient and the time for vaginal opening. No significant changes were detected on eye opening at any dose. However 62.5%（15/24）, 81.25%（26/32）female offspring were permanently absence of vaginal orifice in 750mg・kg-1・d-1 and 1000mg・kg-1・d-1 groups respectively, while the control, 1mg・kg-1・d-1 and 250mg・kg-1・d-1 groups developed normally with vaginal orifices. After covariance adjustment for body weight, which can statistically influenced the age of vaginal opening, differences were found for the age of vaginal opening (F=3.075, P=0.02). The offspring female rats in 250mg/kg group were advanced in vaginal opening time, meanwhile 750mg/kg, 1000mg/kg group showed delayed vaginal opening time compared to the control group. Our results indicated that exposure to DEHP in utero can result in abnormalities of reproductive development such as changes of the age at vaginal opening and vaginal atresia, which could be permanently existent until adulthood.